This section provides background information related to the present disclosure which is not necessarily prior art.
In recent years, development of an advanced driver assistance system (ADAS) for a vehicle has increased. An ADAS includes driver assistance features such as a pre-collision safety (PCS), an adaptive cruise control (ACC), and/or a lane keeping assist (LKA). These driver assistance features are built into the subject vehicle to help the driver avoid a collision, follow a preceding vehicle, and/or keep the subject vehicle in its lane. The ADAS are equipped with one or more sensors, such as an imaging camera, a millimeter-wave/laser radar, and/or a sonar sensor. The sensors detect an environment surrounding the subject vehicle including an approaching object, a crossing pedestrian, a preceding vehicle, and/or lane markers. Based on the environment detected by the sensors, the ADAS controls the subject vehicle automatically by actuating throttle, brake and/or steering to avoid accidents.
Japanese Unexamined Patent Publication No. H10-315800 discloses a driver assistance device equipped with an alterness sensor. The driver assistance device controls a vehicle automatically based on an alterness of the driver which can be detected by one or more sensors. If the alterness level falls below a predefined threshold, the driver assistance device automatically actuates throttle, brake, and/or steering to keep the vehicle running safe or to pull the vehicle to the shoulder of the road.
Generally, the driver can activate or deactivate the driver assistance features individually by, for example, operating a switch which may be disposed at a steering wheel. If the driver turns off the driver assistance feature before starting to drive, the ADAS will not operate until the driver turns on the driver assistance feature. Accordingly, even in a situation in which the driver is distracted or not alert, the ADAS will not operate.